Crash report. Cycles shader graph connect: can only connect closure to closure
If the crash is reporting an issue with shaders then investigate into how the materials are created. Are you connecting a bump map to an add shader node? Nodes have colors that determine what kind of information should be plugged: purple should connect to purple, yellow with yellow and grey with grey... A green input is expecting a green output.

Read: What is the meaning of the color of the node sockets in the node editor?